from flask import Flask, Response


class MyResponse(Response):
    default_mimetype = "applicatin/xml"


app = Flask(__name__)
app.response_class = MyResponse


@app.route("/")
def index():
    return "hello"


@app.route("/custom")
def custom_response():
    return {"key": "value"}


if __name__ == "__main__":
    app.run()
